ref_processor_example

This sample demonstrates an issue with the reference processor in the Swagger parser.

When there is a map property with a map property, and the final type is a reference in another file, then the reference processor does not normalize the reference path relative to the file location of the root contract. This causes a file not found error when running the code generator. The reference should have been updated from ./types.yaml to ./types/types.yaml, which did not happen.

Caused by: java.lang.RuntimeException: Could not find ./types.yaml on the classpath
    at io.swagger.v3.parser.util.ClasspathHelper.loadFileFromClasspath (ClasspathHelper.java:31)
    at io.swagger.v3.parser.util.RefUtils.readExternalRef (RefUtils.java:177)
    at io.swagger.v3.parser.ResolverCache.loadRef (ResolverCache.java:118)
    at io.swagger.v3.parser.processors.ExternalRefProcessor.processRefToExternalSchema (ExternalRefProcessor.java:51)
    at io.swagger.v3.parser.processors.SchemaProcessor.processReferenceSchema (SchemaProcessor.java:202)
    at io.swagger.v3.parser.processors.SchemaProcessor.processAdditionalProperties (SchemaProcessor.java:74)
    at io.swagger.v3.parser.processors.SchemaProcessor.processSchemaType (SchemaProcessor.java:61)
    at io.swagger.v3.parser.processors.SchemaProcessor.processArraySchema (SchemaProcessor.java:188)
    at io.swagger.v3.parser.processors.SchemaProcessor.processSchemaType (SchemaProcessor.java:47)
    at io.swagger.v3.parser.processors.SchemaProcessor.processPropertySchema (SchemaProcessor.java:105)
    at io.swagger.v3.parser.processors.SchemaProcessor.processSchemaType (SchemaProcessor.java:54)
    at io.swagger.v3.parser.processors.SchemaProcessor.processSchema (SchemaProcessor.java:39)
    at io.swagger.v3.parser.processors.ComponentsProcessor.processSchemas (ComponentsProcessor.java:222)
    at io.swagger.v3.parser.processors.ComponentsProcessor.processComponents (ComponentsProcessor.java:72)
    at io.swagger.v3.parser.OpenAPIResolver.resolve (OpenAPIResolver.java:50)
    at io.swagger.v3.parser.OpenAPIV3Parser.readLocation (OpenAPIV3Parser.java:53)
    at io.swagger.parser.OpenAPIParser.readLocation (OpenAPIParser.java:19)

See the test contract which has different combinations of array and map schemas. To reproduce, clone this project and execute.

# Code generation requires maven 3.2.5 or later.
mvn clean compile

In researching, the problem lies in an incomplete implementation of the method processProperties in the ExternalRefProcessor. The method does not recurse in all situations, so depending on the contract, it can lead to an incomplete reference resolution.

I was able to fix the issue by replacing that method with these 3 methods:

    private void processProperty(Schema subProp, String file) {
        if (subProp != null) {
            if (StringUtils.isNotBlank(subProp.get$ref())) {
                processRefSchema(subProp, file);
            }
            if (subProp.getProperties() != null) {
                processProperties(subProp.getProperties(), file);
            }
            if (subProp instanceof ArraySchema) {
                processProperty(((ArraySchema) subProp).getItems(), file);
            }
            if (subProp.getAdditionalProperties() instanceof Schema) {
                processProperty(((Schema) subProp.getAdditionalProperties()), file);
            }
            if (subProp instanceof ComposedSchema) {
                ComposedSchema composed = (ComposedSchema) subProp;
                processProperties(composed.getAllOf(), file);
                processProperties(composed.getAnyOf(), file);
                processProperties(composed.getOneOf(), file);
            }
        }
    }

    private void processProperties(Collection<Schema> subProps, String file) {
        if (subProps != null) {
            for (Schema subProp : subProps) {
                processProperty(subProp, file);
            }
        }
    }

    private void processProperties(Map<String, Schema> subProps, String file) {
        if (subProps != null) {
            processProperties(subProps.values(), file);
        }
    }